The Kaluza Klein graviton as conclusive evidence for extra dimensions at the LHC

The discovery of Kaluza-Klein (KK) gravitons at the Large Hadron Collider (LHC) is considered conclusive evidence for extra dimensions. Such particles would have the same properties as the original four-dimensional graviton; however, they would be massive. Due to their spin-2 nature, KK gravitons could be identified at colliders using angular distributions of final states; however, other new physics scenarios, such as a new strongly-coupled sector, could give rise to spin-2 resonances which would act as impostors. Since both KK gravitons and their impostors are found to have the same couplings to the Standard Model (SM) up to dimension-five operators, their decay products also do not aid in distinguishing between the two. Alternatively, the ratio of branching ratios to photons and gluons can be used as the identification procedure. This proposal also has holographic consequences, as it is a manifestation of the breakdown of the duality between weakly-coupled AdS theories in five dimensions and strongly-coupled four-dimensional conformal theories.